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Steel C30-CD vs C30-HR

Steel · C30 temper comparison

C30-CD and C30-HR are two conditions of the same steel grade, C30: CD (cold drawn) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. C30-CD is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 260 MPa (37.7 ksi) for C30-HR, about 69% more; tensile strength follows at 525 MPa (76.1 ksi) vs 470 MPa (68.2 ksi). In exchange, C30-HR is the more ductile: elongation 20% versus 12% for C30-CD, and C30-CD is harder (149 HB vs 137 HB).

C30-CDChoose it when strength drives the design.

C30-HRChoose it when the part is bent, formed or impact-loaded.

C30-CD vs C30-HR: properties

C30-CDC30-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

525 MPa76.1 ksi
470 MPa68.2 ksi

Yield Strength (0.2% offset)

440 MPa63.8 ksi
260 MPa37.7 ksi

Elongation at Break

12%
20%

Reduction in Area

35%
42%

Shear Strength

315 MPa45.7 ksi
285 MPa41.3 ksi

Fatigue Strength (Endurance Limit)

250 MPa36.3 ksi
225 MPa32.6 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

149 HB
137 HB

Hardness, Rockwell B

80 HRB
76 HRB

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 345 MPa50 ksi · Fracture Toughness (K_IC) 60 MPa·√m54.6 ksi·√in · Hardness, Vickers 157 HV

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,512°C2,754 °F

Thermal

How each material carries heat and how hot it can run.

Same in both: Thermal Conductivity 50 W/m·K28.9 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10 % IACS · Electrical Resistivity 1.7×10⁻⁷ Ω·m6.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

65 / 100
58 / 100

Weldability

65 / 100
68 / 100

Formability (cold)

35 / 100
55 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 70% · Brazeability / Solderability 70 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 30%

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleC30

C30-CD vs C30-HR — frequently asked

Is C30-CD stronger than C30-HR?

Yes. C30-CD has a typical yield strength of 440 MPa (63.8 ksi) against 260 MPa (37.7 ksi) for C30-HR — about 69% more. Tensile strength is 525 MPa (76.1 ksi) vs 470 MPa (68.2 ksi).

Which condition does FabDigit quote by default, CD or HR?

N is the default C30 condition in the FabDigit quote flow (neither CD nor HR). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, C30-CD or C30-HR?

C30-CD, by a small margin. Both rate good for machinability — 65/100 against 58/100 for C30-HR.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C30-CD and C30-HR side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.